From Forum Nokia Wiki

On Nokia mobile phones, you can key in certain codes in standby mode that will display information or make the phone perform certain operations. This is a reference of such codes. Note that not all codes apply to all phone models

• "*#0000#" - displays firmware version (and date) and phone model

• "*#06*" - displays IMEI

• "*3370#" - activates Enhanced Full Rate Codec (EFR); better sound quality for slightly reduced talk time

• "#3370#" - deactivates Enhanced Full Rate Codec

• "*#4720#" - activates Half Rate Codec; worse sound quality for better talk time. Same code deactivates it

• "*#9999#" - displays firmware version if *#0000# doesn't work; only works on some models

• "*#2640#" - displays phone security code

• "*#7780#" - restore factory settings

• "*#92702689#" - displays total duration of phone calls

• "*#43#" - check the "Call Waiting" status

• "*#61#" - check the number that "On No Reply" calls are diverted to

• "*#62#" - check the number that "Divert If Unreachable (no service)" calls are diverted to

• "*#67#" - check the number that "On Busy Calls" are diverted to

• "**21*number#" - turn on "All Calls" diverting to the phone number entered

• "**61*number#" - turn on "No Reply" diverting to the phone number entered

• "**67*number#" - turn on "On Busy" diverting to the phone number entered

Related Internal Link

• Star-hash codes